Seals are required at various points in an aircraft. When the seals are used to form an aerodynamic seal then they are exposed to air flow, which can induce a rapid movement of the seal known as ‘seal flutter’. Seal flutter induces parasitic drag and negatively affects the performance of the aircraft. In modern aircraft, parasitic drag forms upwards of 12% of the total drag during cruise and there is consequently a focus on reducing these effects.
In existing seals, a strip of stiffening fabric material may be used to impart stiffness to the seal. However, if the seal is too stiff then it may be difficult to install and/or may be too stiff to maintain a seal at all times and/or may be unsuitable for forming an aerodynamic seal.